Breaking a GZE piston or rod

[RonRob]

Sure thing!
I am new to the power level that I am getting and I guess I invision adding a few degrees and next thing you know BOOM! I even take out my plugs after hard runs and do a compression check every few weeks to see how shes doing. Always equal on all four and plugs are in good shape gapped at 7mm.

Ron

[kingmick]

they are not good for 450hp-500hp unless its for a very short time and there is no problems with fueling or spark at all! ive seen a few broken ones from over reving and leaning out.
even cast pistons will handle big power but there is no saftey margin and they wont last as long.
when building an engine for big boost you build it strong to handle the things like an injector playing up and leaning out a pot etc. the stronger parts tend to give a little bit more insurance and last longer under harder conditions.
Rods are in the same vote! depends what sort of driving you are doing, Drag racing you can get away with Alloy rods because you are not engine breaking which puts a huge twist load on rods. Dyno Queen the standard rods can last aswell because of light decel loads compared to the track and street.
It all comes down to Insurance.
Everything wears and can be broken.

[30psi 4agte]

Kingmick I beg to differ ! Im not saying you are wrong as this is what i have herd too BUT
I had done numerous runs of 283 rwkw and then started playing with Nos on the cooler and managed 313.7rwkw @ 6700 (Previous 283 was @ 8350) before this happend a CATASTROPHIC lean out.
Note i dont count the 313.7 as a true power figure cos anyone can make Sh1t loads of power and blow up motors!

I had always wondered about the pistons and rods but after this I will never worry again!!
I thought i would have broke a piston or bent a rod for sure but they were PERFECT

I guess 313.7kw (420 hp) would be 500 hp at fly if not more?

[RonRob]

That is alot of power you are making. Is your bottom end stock gze bigport rods and low comp gze pistons? Arp bolts on everything or factory bolts? Stock headgasket or aftermarket? Amazing and very inspirational to know our engines can take a pounding stock with a proper tune.

Ron

[Vios-GT_07]

I salute anyone who can break a 4A-G(Z)E's piston, rod, or crankshaft. Coz i've seen the craziest of things done to a 4A-GE motor including turbos, Superchargers, heaps of timing, out of tune etc etc leading up to blown heads, shredded gaskets and the likes, but have never seen anyone even dent the internals. Even the block for that matter. I've even seen the old block get bored out to the end of its life i.e. cannot be bored anymore, and having travelled more than 600,000 kms, once with oversized pistons and constantly getting thrashed around.

[oldcorollas]

they can definitely break. back when i did the piston analysis i had two such examples. i think on one the ring lands broke and the other... well.. at least the rod had been spat out
so yes, they do break.

[Vios-GT_07]

oh well.. i salute you..

but seriously i've had a 4A-GZE bigport in the old spoontah, running Haltech E6A , the basic dumb ECU and i've ran it with full boost and 28 degrees of timing, nowhere near breaking point. Ran it slightly rich though but that's about it.

In fact i've revved a 4A-C right to the end to see where it'd break coz i already prepped a 4A-GE for it. Nope couldn't break it. I've had a mate drain the water and oil in his 4A-C. Just broke the HG when it finally died (after 2 hours, of red line). one HG replacement later and it still ran.

[Ghetto-AW11]

I broke the ring lands on my stock gze with 110,000 on it. The sucker overboosted due to a split vacumline running to the boost conroller, hit somewhere in the region of 28psi + and had not been tuned for that much boost. 1st and 4th ring lands.

[kingmick]

oh well.. i salute you..

but seriously i've had a 4A-GZE bigport in the old spoontah, running Haltech E6A , the basic dumb ECU and i've ran it with full boost and 28 degrees of timing, nowhere near breaking point. Ran it slightly rich though but that's about it.

In fact i've revved a 4A-C right to the end to see where it'd break coz i already prepped a 4A-GE for it. Nope couldn't break it. I've had a mate drain the water and oil in his 4A-C. Just broke the HG when it finally died (after 2 hours, of red line). one HG replacement later and it still ran.

so a 4ac run redline for two hours and it did a head gasket, with no oil or water in it! rvrn no load i find this very intresting! lol

[kingmick]

I broke the ring lands on my stock gze with 110,000 on it. The sucker overboosted due to a split vacumline running to the boost conroller, hit somewhere in the region of 28psi + and had not been tuned for that much boost. 1st and 4th ring lands.

hahaha well you shouldnt drive it when it over boosts! { and im giving a mate a ribbing}.

[Ghetto-AW11]

i should really blame the person who put it togeather? Who was that again?

[kingmick]

i should really blame the person who put it togeather? Who was that again?

I hear he is a ledgend! not his fault, he didnt drive it over boosted!hahahaahah

[Vios-GT_07]

so a 4ac run redline for two hours and it did a head gasket, with no oil or water in it! rvrn no load i find this very intresting! lol

how do you kill a 4AC? i mean really crack the piston or something stupid with the rod?

GZE is durable but by no means not indestructable. However in standard form with minimal mods (cams, piggyback, quad throttle) it goes a long way. I had a mate overseas who had a spoontah with a 4A-GE, blew 2 gearboxes in a year from drift and race events. Yet never had to do anything to the engine except maintenance. Compression barely dropped 5 psi in each chamber, and we're talking race once every week or two weeks for the whole year, heavy acceleration, high-revs the works.

Similarly i know another guy who's got an AW11 GZE with an auto transmission that's gone through a transmission and blower, two HGs among many others. Yet at 200,000 kms is still using factory pistons and rods. Technically it's about close to the end, but sure doesn't feel like it.

well i'm not saying that 4A-G(Z)E is not indestructable, and it is only a 1.6 so there are limits. However i have to agree that it's a pretty tough and durable motor considering it's more than 20 years old since being introduced. just my 2 cents..

[kingmick]

be more a case of grabing the bore or grabing a crank. there are no engine that i know of that toyota make that can run without oil for long at all!
under load at redline! all engines will die in the blick of an eye!

[Vios-GT_07]

be more a case of grabing the bore or grabing a crank. there are no engine that i know of that toyota make that can run without oil for long at all!
under load at redline! all engines will die in the blick of an eye!

true.. the dude could have exaggerated about not having oil.. but it's not my story

the place where i used to work once did a service on a camry and the apprentice started the car without filling back the oil or putting back the sump nut. Car ran for 10 mins or so literally before it started making really bad noises. stopped it straight away, fill back the oil, filter etc and yea it still goes fine.